The woman may not be aware that she is pregnant. These characteristic symptoms occur in ruptured ectopic pregnancies (those accompanied by severe internal bleeding) and non-ruptured ectopic pregnancies. However, while these symptoms are typical for an ectopic pregnancy, they do not mean an ectopic pregnancy is necessarily present and could represent other conditions. In fact, these symptoms also occur with a threatened abortion (miscarriage) in nonectopic pregnancies.

    The signs and symptoms of an ectopic pregnancy typically occur six to eight weeks after the last normal menstrual period, but they may occur later if the ectopic pregnancy is not located in the Fallopian tube. Other symptoms of pregnancy (for example, nausea and breast discomfort, etc.) may also be present in ectopic pregnancy. Weakness, dizziness, and a sense of passing out upon standing can (also termed near-syncope) be signs of serious internal bleeding and low blood pressure from a ruptured ectopic pregnancy and require immediate medical attention. Unfortunately, some women with a bleeding ectopic pregnancy do not recognize they have symptoms of ectopic pregnancy. Their diagnosis is delayed until the woman shows signs of shock (for example, low blood pressure, weak and rapid pulse, pale skin and confusion) and often is brought to an emergency department. This situation is a medical emergency.

    Age: Ectopic pregnancy can occur in any woman, of any age, who is ovulating and is sexually active with a male partner. The highest likelihood ectopic pregnancy occurs in women aged 35-44 years.

    History: The greatest risk factor for an ectopic pregnancy is a prior history of an ectopic pregnancy. Fallopian tube abnormalities: Any disruption of the normal architecture of the Fallopian tubes can be a risk factor for a tubal pregnancy or ectopic pregnancy in other locations.

    Previous gynecological surgeries: Previous surgery on the Fallopian tubes such as tubal sterilization or reconstructive, procedures can lead to scarring and disruption of the normal anatomy of the tubes and increases the risk of an ectopic pregnancy.

    Infection: Infection in the pelvis (pelvic inflammatory disease) is another risk factor for ectopic pregnancy. Pelvic infections are usually caused by sexually-transmitted organisms, such as Chlamydia or N. gonorrhoeae, the bacteria that cause gonorrhea. However, non-sexually transmitted bacteria can also cause pelvic infection and increase the risk of an ectopic pregnancy. Infection causes an ectopic pregnancy by damaging or obstructing the Fallopian tubes. Normally, the inner lining of the Fallopian tubes is coated with small hair-like projections called cilia. These cilia are important to transport the egg smoothly from the ovary through the Fallopian tube and into the uterus. If these cilia are damaged by infection, egg transport becomes disrupted. The fertilized egg can settle in the Fallopian tube without reaching the uterus, thus becoming an ectopic pregnancy. Likewise, infection-related scarring and partial blockage of the Fallopian tubes can also prevent the egg from reaching the uterus.